Wavelet Analysis of PK2600 Measurement Data on Core-Rod

2012 ◽  
Vol 571 ◽  
pp. 551-554 ◽  
Author(s):  
Hong Sheng Li ◽  
Zhen Yu Li
Keyword(s):  
Vapor Deposition ◽  
Measurement Data ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Refractive Index Profile ◽  
Index Profile ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
The Core ◽  
Core Rod

The Core Rod made by Plasma Chemical Vapor Deposition process is measured by PK2600 for Refractive Index Profile. The measurement data is very important to justify the core rod quality. A method based on DWT is presented in this paper to discover some information which is difficult to emerge according to conventional way. The analysis result can be used to optimize the core-rod making process.

Optical emission spectroscopy during the bias-enhanced nucleation of diamond microcrystals by microwave plasma chemical vapor deposition process

1996 ◽  
Vol 11 (11) ◽  
pp. 2852-2860 ◽  
Author(s):  
H. C. Barshilia ◽  
B. R. Mehta ◽  
V. D. Vankar
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Emission Spectroscopy ◽  
Optical Emission Spectroscopy ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Optical Emission ◽  
Deposition Process ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition

Microwave plasma chemical vapor deposition (MWPCVD) process has been used to grow diamond thin films on silicon substrates from CH4–H2 gas mixture. Bias-enhanced nucleation (BEN) pretreatment has been used to increase the density of diamond nuclei. Various species in the CH4–H2 plasma have been identified using optical emission spectroscopy (OES), and their effect on the film microstructure has been studied. During the pretreatment process the emission intensities of CH, CH+, C2, H, and H2* species have been found to increase significantly for a negative dc bias voltage |VB| > 60 V. The higher concentration of excited species and the associated effects play a significant role in the growth process. A very thin layer of a-C containing predominant sp3 bonded carbon species in the initial stages of the growth is found to be present in these films. The microstructure of the films has been found to be very sensitive to the biasing conditions.

ANN-Model for Plasma Chemical Vapor Deposition Process

2013 ◽  
Vol 699 ◽  
pp. 92-95
Author(s):  
Zhen Yu Li ◽  
Hong Sheng Li
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Chemical Vapor Deposition Process ◽  
Ann Model ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
Process Gas ◽  
Vapor Deposition Process

Plasma Chemical Vapor Deposition process is one of the main process to make optical fiber core-rod. In this process, gas flow, pressure, furnace temperature, reflective microwave power , resonator moving speed and deposition rate are dependant aspects. An artificial neural network model is set up to describe the relationship of variables in the process, and also verified by the experiment and production. Based on the ANN-model, the process recipe setting is illustrated in the paper.

A New Type of Resonator Designed for Plasma Chemical Vapor Deposition

2011 ◽  
Vol 121-126 ◽  
pp. 642-646
Author(s):  
Zhen Yu Li ◽  
Hong Sheng Li
Keyword(s):  
Chemical Vapor Deposition ◽  
Optical Fiber ◽  
Deposition Rate ◽  
Vapor Deposition ◽  
Fiber Quality ◽  
Chemical Vapor ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
New Type ◽  
Core Rod

Plasma Chemical Vapor Deposition ( PCVD ) is an important application in making optical fiber core rod. The resonator is the key part for PCVD application. But the existing resonator have several serious disadvantages: its working is not stable; the size of deposited substrate tube is small(Ø31mm); the deposition rate is low(2.5g/min) and the deposition effect is unsymmetrical; the fabrication of the resonator is very difficult and expensive. Therefore, a new type of resonator, a cylinder resonator, is designed to overcome the above disadvantages. The cylinder resonator supports bigger substrate tube (Max Ø60mm) and higher deposition rate(3.2g/min) than existing ones, while its working is also more stable. Since the structure is more simple, the fabrication is easier and cheaper. The corresponding microwave theoretical method of the new resonator designing is also introduced with the necessary computer simulation, as well as test running. And TE111 mode microwave is the Fundamental Mode of the cylinder resonator. The cylinder resonator has been applied in normal production for 4 years, which is better for bigger size core rod making, improving the optical fiber quality and saving cost. It is estimated, after modification with the cylinder resonator and 10kW microwave generator, a PCVD lathe can yield 30% more rods than before.

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